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1.
J Anat ; 239(6): 1318-1335, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34268788

RESUMO

Describing osteological development is of great importance for understanding vertebrate phenotypic variations, form-functional transitions and ecological adaptations. Anurans exhibit dramatic changes in their morphology, habitat preferences, diet and behaviour between the tadpole and frog stages. However, the anatomical details of their cranial and postcranial development have not been extensively studied, especially in Microhylidae. In this work, we studied the microhylid Microhyla fissipes, commonly known as the ornamented pygmy frog, a small-sized frog with fast metamorphosis. Its osteological development was comprehensively described based on 120 cleared and stained specimens, including six tadpoles for each stage between 28 and 45, six juveniles and six adults. Additionally, 22 osteological traits of these specimens involved in food acquisition, respiration, audition and locomotion were selected and measured to reflect the changes in tadpole ecological functions during metamorphosis. Our study provides the first detailed qualitative and quantitative developmental information about these structures. Our results have confirmed that skeletal elements (viz., neopalatines, omosternum, clavicles and procoracoids) absent in adults are not detected during development. Our data reveal that morphologically, radical transformations of the cranial structures related to feeding and breathing are completed within stages 42-45 (72 h), but the relative length and width of these skeletons have changed in earlier stages. The postcranial skeletons correlated with locomotion are well developed before stage 42 and approach the adult morphology at stage 45. Indeed, the relative length of the pectoral girdle and forelimb reaches the adult level at stage 42 and stage 45, respectively, whereas that of the vertebral column, pelvic girdle and hind limbs increases from their appearance until reaching adulthood. Based on published accounts of 19 species from Neobatrachia, Mesobatrachia and Archaeobatrachia, cranial elements are among the first ossified skeletons in most studied species, whereas sphenethmoids, neopalatines, quadratojugals, mentomeckelians, carpals and tarsals tend to ossify after metamorphosis. These results will help us to better understand the ecomorphological transformations of anurans from aquatic to terrestrial life. Meanwhile, detailed morphological and quantitative accounts of the osteological development of Microhyla fissipes will provide a foundation for further study.


Assuntos
Anuros , Metamorfose Biológica , Animais , Membro Anterior , Larva , Osteologia
2.
World J Gastrointest Surg ; 13(2): 153-163, 2021 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-33643535

RESUMO

BACKGROUND: Preoperative portal vein embolization (PVE) is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant. PVE induces hypertrophy of the future liver remnant (FLR) and a shift of the functional reserve to the FLR. However, whether the increase of the FLR volume (FLRV) corresponds to the functional transition after PVE remains unclear. AIM: To investigate the sequential relationship between the increase in FLRV and functional transition after preoperative PVE using 3-dimensional (3D) computed tomography (CT) and 99mTc-galactosyl-human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT) fusion images. METHODS: Thirty-three patients who underwent major hepatectomy following PVE at the Department of Gastroenterological Surgery I, Hokkaido University Hospital between October 2013 and March 2018 were enrolled. Three-phase dynamic multidetector CT and 99mTc-GSA SPECT scintigraphy were performed at pre-PVE, and at 1 and 2 wk after PVE; 3D 99mTc-GSA SPECT CT-fused images were constructed from the Digital Imaging and Communications in Medicine data using 3D image analysis system. Functional FLRV (FFLRV) was defined as the total liver volume × (FLR volume counts/total liver volume counts) on the 3D 99mTc-GSA SPECT CT-fused images. The calculated FFLRV was compared with FLRV. RESULTS: FFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE (P < 0.01). The increase in FFLRV and FLRV was 55.1% ± 41.6% and 26.7% ± 17.8% (P < 0.001), respectively, at 1 wk after PVE, and 64.2% ± 33.3% and 36.8% ± 18.9% (P < 0.001), respectively, at 2 wk after PVE. In 3 of the 33 patients, FFLRV levels decreased below FLRV at 2 wk. One of the three patients showed rapidly progressive fatty changes in FLR. The biopsy at 4 wk after PVE showed macro- and micro-vesicular steatosis of more than 40%, which improved to 10%. Radical resection was performed at 13 wk after PVE. The patient recovered uneventfully without any symptoms of pos-toperative liver failure. CONCLUSION: The functional transition lagged behind the increase in FLRV after PVE in some cases. Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE.

3.
Eur Child Adolesc Psychiatry ; 28(7): 957-971, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30506419

RESUMO

The clinical significance and the prognostic value of clinical high risk (CHR) for psychosis, while substantially corroborated in adults, remains less firmly established in children and early adolescents. This follow-up study, developed within the Reggio Emilia At Risk Mental States project, is meant to contribute to the reduction of such lacuna, and has two main aims: (1) to characterize the clinical profile of help seekers [stratified in non-CHR, CHR and first episode psychosis (FEP)] referred to child-adolescent mental health services; and (2) to monitor the cumulative transition rate from CHR to FEP in adolescents at the follow-up of 12 and 24 months. 112 adolescents (aged 13-18 years) were assessed with the Comprehensive Assessment of At-Risk Mental States and the Schizophrenia Proneness Instrument, Child and Youth version. 51 subjects met CHR criteria (45.5% of the sample) and 33 subjects met FEP criteria (29.5%) at baseline. The criterial transition rate from CHR to FEP was 7% over 12 months and 13% over 24 months; higher rates of cumulative transition were detected when also functional transition (indexed by the consensual introduction of antipsychotic medication by the treating clinical staff) was considered. The identification of CHR for psychosis in help-seeking adolescents is feasible and clinically relevant. Studies conducted in real world, publicly funded components of the national health system, should take into consideration not only criterial, psychometric transition, but also functional equivalents of transition.


Assuntos
Transtornos Psicóticos/psicologia , Adolescente , Feminino , Seguimentos , Humanos , Masculino
4.
Rev. pesqui. cuid. fundam. (Online) ; 10(4): 1164-1168, out.-dez. 2018.
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-915593

RESUMO

Objective: To describe how the nursing professional handles new assignments and responsibilities, identify and discuss the factors that facilitate and facilitate this transition to nursing work. Method: Descriptive, exploratory study with a qualitative approach. Participants were thirteen nursing technicians who underwent functional transition and currently perform functions as nurses. It presents as scenario, surgical units of a university hospital, in rio de janeiro. The ethical and legal aspects of Resolution No. 466/2012 of the CNS approved by the CEP, under No. 1,432,069, were respected. The semi-structured interview was used to analyze the data, and content analysis was performed. Results: It presents as categories: the professional nursing technician and the functional transition for nurses and the facilitating and hindering factors in the functional transition. Conclusion: The functional transition meets the need of the technician in the search for scientific knowledge, professional growth and personal evolution


Objetivo: Descrever como o profissional de enfermagem lida com novas atribuições e responsabilidades, identificar e discutir os fatores facilitadores e dificultadores dessa transição para o trabalho de enfermagem. Método: Estudo descritivo, exploratório com abordagem qualitativa. Os participantes foram treze técnicos de enfermagem que passaram pela transição funcional e atualmente desenvolvem funções enquanto enfermeiros. Apresenta como cenário, unidades cirúrgicas de um hospital universitário, no rio de janeiro. Foram respeitados os aspectos éticos e legais da resolução nº466/2012 do CNS aprovado pelo CEP, com o nº 1.432.069. Utilizou-se a entrevista semiestruturada, para análise dos dados, realizou-se a análise de conteúdo. Resultados: Apresenta como categorias: o profissional técnico de enfermagem e a transição funcional para enfermeiro e os fatores facilitadores e dificultadores na transição funcional. Conclusão: A transição funcional atende a necessidade do técnico na busca por conhecimento científico, crescimento profissional e evolução pessoal


Objetivos: describir cómo el profesional de enfermería trata con nuevas asignaciones y responsabilidades, identificar y debatir los factores facilitadores y obstaculizadores de esta transición al trabajo de enfermería. Método: estudio descriptivo, exploratorio con enfoque cualitativo. Los participantes fueron trece técnicos de enfermería que pasaron por la transición funcional y actualmente desarrollan funciones como enfermeros. Presenta como escenografía, unidades quirúrgicas de un hospital universitario en Río de Janeiro. Se respetaron los aspectos éticos y jurídicos de la resolución no 466/2012 del CNS aprobada por el CEP, con el párrafo 1.432.069. La entrevista interestructurada se utilizó para el análisis de los datos, se realizó el análisis del contenido. Resultados: presenta como categorías: el técnico profesional de enfermería y la transición funcional a la enfermería y a los facilitadores y factores que dificultan la transición funcional. Conclusión: la transición funcional satisface la necesidad del técnico en la búsqueda para el conocimiento científico, el crecimiento profesional y la evolución personal


Assuntos
Humanos , Masculino , Feminino , Mobilidade Ocupacional , Técnicos de Enfermagem , Enfermeiras e Enfermeiros , Brasil , Equipe de Enfermagem
5.
Plant Cell Physiol ; 56(7): 1264-71, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26063394

RESUMO

Peroxisomes are present in almost all plant cells. These organelles are involved in various metabolic processes, such as lipid catabolism and photorespiration. A notable feature of plant peroxisomes is their flexible adaptive responses to environmental conditions such as light. When plants shift from heterotrophic to autotrophic growth during the post-germinative stage, peroxisomes undergo a dynamic response, i.e. enzymes involved in lipid catabolism are replaced with photorespiratory enzymes. Although the detailed molecular mechanisms underlying the functional transition of peroxisomes have previously been unclear, recent analyses at the cellular level have enabled this detailed machinery to be characterized. During the functional transition, obsolete enzymes are degraded inside peroxisomes by Lon protease, while newly synthesized enzymes are transported into peroxisomes. In parallel, mature and oxidized peroxisomes are eliminated via autophagy; this functional transition occurs in an efficient manner. Moreover, it has become clear that quality control mechanisms are important for the peroxisomal response to environmental stimuli. In this review, we highlight recent advances in elucidating the molecular mechanisms required for the regulation of peroxisomal roles in response to changes in environmental conditions.


Assuntos
Luz , Peroxissomos/efeitos da radiação , Proteínas de Plantas/metabolismo , Plantas/efeitos da radiação , Protease La/metabolismo , Autofagia/efeitos da radiação , Modelos Biológicos , Oxirredução/efeitos da radiação , Peroxissomos/enzimologia , Peroxissomos/metabolismo , Plantas/metabolismo , Transporte Proteico/efeitos da radiação , Proteólise/efeitos da radiação
6.
Plant Signal Behav ; 9(5): e28838, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24739336

RESUMO

Functional transition of glyoxysomes to leaf peroxisomes is observed in greening cotyledons. Glyoxysomal proteins are rapidly degraded and leaf-peroxisomal proteins are transported into peroxisomes after cotyledons are exposed to light, but the molecular mechanisms underlying these processes remain unclear. We recently discovered that two degradation pathways are involved in the functional transition of peroxisomes using Arabidopsis thaliana. Lon protease 2 (LON2) is responsible for the degradation of glyoxysomal proteins inside peroxisomes, and, in parallel, autophagy eliminates damaged or obsolete peroxisomes. A double mutant defective in both the LON2- and autophagy-dependent degradation pathways accumulated glyoxysomal proteins after the cotyledons became green. Our study also demonstrated that the LON2- and autophagy-dependent pathways are interdependent, with the chaperone function of LON2 suppressing autophagic peroxisome degradation. Moreover, the peptidase domain of LON2 interferes with the suppression of autophagy, indicating that autophagy is regulated by intramolecular modulation between the proteolysis and chaperone functions of LON2.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Autofagia , Chaperonas Moleculares/metabolismo , Peptídeo Hidrolases/metabolismo , Peroxissomos/metabolismo , Glioxissomos/metabolismo , Redes e Vias Metabólicas , Modelos Biológicos
7.
Plant Cell Physiol ; 55(3): 482-96, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24492254

RESUMO

Balancing repair and degradation is essential for maintaining organellar and cellular homeostasis. Peroxisomes are ubiquitous organelles in eukaryotic cells that play pivotal roles in cell survival. However, the quality control mechanism used to maintain peroxisomes is unclear. Here, we demonstrate that LON protease 2 (LON2), which is encoded by ABERRANT PEROXISOME MORPHOLOGY 10 (APEM10), is responsible for the functional transition of peroxisomes with autophagy. The Arabidopsis apem10 mutant displayed accelerated peroxisome degradation and a dramatically reduced number of peroxisomes. LON2 deficiency caused enhanced peroxisome degradation by autophagy, and peroxisomal proteins accumulated in the cytosol due to a decrease in the number of peroxisomes. We also show the proteolytic consequence of LON2 for the degradation of peroxisomal proteins, and we demonstrated that unnecessary proteins are eliminated by LON2- and autophagy-dependent degradation pathways during the functional transition of peroxisomes. LON2 plays dual roles as an ATP-dependent protease and a chaperone. We show that the chaperone domain of LON2 is essential for the suppression of autophagy, whereas its peptidase domain interferes with this chaperone function, indicating that intramolecular modulation between the proteolysis and chaperone functions of LON2 regulates degradation of peroxisomes by autophagy.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Autofagia/fisiologia , Chaperonas Moleculares/metabolismo , Peroxissomos/metabolismo , Protease La/metabolismo , Arabidopsis/enzimologia
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